Collector of small solid particles



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United States Patent 3,506,042 COLLECTOR OF SMALL SOLID PARTICLES Warren H. Zuercher, Seattle, Wash., assignor to Stetson- Ross Machine Company, Inc., Seattle, Wash., a corporation of Washington Filed Apr. 17, 1967, Ser. No. 631,375 Int. Cl. B27b 5/34, 5/00, 5/28 US. Cl. 14337 23 Claims ABSTRACT OF THE DISCLOSURE In the working of a solid, there is often produced small solid particles of the solid. These collect in the working area and around the working tool and become a nuisance and a hazard. For example, in the sawing of lumber to specified lengths, there is used a plurality of saws. These saws are arranged in a spaced-apart pattern. Naturally, the saws produce quantities of sawdust. From a safe working standpoint, and also for ease of maintenance of the equipment, it is desirable to remove the sawdust. In this invention there is provided an exhaust hood with a gathering means connecting with the exhaust hood, for collecting the sawdust. This gathering means is positioned near the saw or the working tool. Now, there must be an opening in the exhaust hood so that the gathering means can communicate with the exhaust hood. If all of these openings are continually open, the diiferential gas pressure between that in the exhaust hood and that in the working area near the tool is not sufficiently great to insure the movement of the sawed small solid particles in the Working area into the exhaust hood. This invention is designed to provide a means and a method for closing the opening in the exhaust hood when a saw is not sawing and to open said opening in the exhaust hood when a saw is sawing. As a result, there is a greater dilferential in the gas pressure between the gas in the working area and the gas in the exhaust hood as compared with the situation when all of the openings in the exhaust hood are open. This means that more of the small solid particles will move from the working area into the exhaust hood. Accordingly, it is an object of this invention to provide an exhaust means for removing small solid particles from a working area; a further object is to provide a gathering means for said solid particles and which gathering means is as close as reasonable to the working tool; a still further object is to provide a method and apparatus for removing small solid particles from a working area and which method and apparatus make efficient utilization for the use of a dilferential gas pressure between the working area and the gas pressure in the exhaust hood; a still further and important object is the provision of a method and apparatus for the efiicient maintenance of a gas differential pressure between that of the working area and that in the exhaust hood so as to lessen the power requirement for the removal of the small solid particles from the working area; and, a still further and important object is to provide apparatus for removing the small solid particles from the working area and which apparatus has a gathering means which is above the traveling line of the incoming solid such as lumber.

These and other important objects and advantages of the invention will be more particularly brought forth upon reference to the accompanying drawings, the detailed description of the invention and the appended claims.

In the drawings:

In FIGURE 1 there is illustrated a specific embodiment of the invention constructed in accordance with the preferred teaching thereof and which figure shows an exhaust hood, a gathering means positioned near the working tool, a dampner for removably covering an opening in said exhaust hood and shows the working tool in contact with a solid and the dampner in an open position so as to allow small solid particles to pass through the opening into the exhaust hood;

. In FIGURE 2 there is illustrated the invention with the working tool out of contact with a solid and which shows the dampner covering the opening in the exhaust hood;

FIGURE 3, on an enlarged scale, illustrates the opening in the exhaust hood, a dampner covering part of said opening, and a setscrew for positioning said dampner when the dampner is at rest or in an unopened position;

FIGURE 4, taken on line 4-4 of FIGURE 1, is a horizontal cross-sectional view illustrating the working,

tool, and the means for moving the working tool towards the solid to be worked and away from the solid to be worked;

FIGURE 5, taken on line 55 of FIGURE 1, is a vertical lateral cross-sectional view illustrating the gathering means and its relationship with the working tool so as to have the gathering means positioned closely to said Working tool for picking up small solid particles;

FIGURE 6, taken on line 66 of FIGURE 1, is a horizontal cross-sectional view illustrating the exhaust hood, the dampner for opening and closing an opening in said exhaust hood, and an arm for moving said dampner;

FIGURE 7, taken on line 77 of FIGURE 6, is a side-elevational view illustrating the exhaust hood, the dampner for opening and closing the opening in said exhaust hood, and the means for moving said dampner and illustrates said dampner in an open position so that small solid particles can move into the exhaust hood;

FIGURE 8 is a cross-sectional vertical view showing the dampner in the exhaust hood in a closed position so as to preclude the flow of particles into the exhaust hood; and

FIGURE 9, taken on line 9-9 of FIGURE 1, is a vertical lateral cross-sectional view illustrating the arrangement of the working tool, the gathering means for gathering small solid particles in the area of the working tool and also the hold-down assembly for positioning the solid.

In the drawings it is seen that the subject matter of the invention comprises a working tool which is a saw. The saw is used to saw lumber into desired lengths. It is to be realized that, in a sawmill, there are cut-off saws for cutting lumber to appropriate lengths. Actually, there are a plurality of these cut-oif saws. In this particular installation, there are eleven cut-off saws arranged in a line for cutting the lumber to suitable lengths. For example, there-- m-ay be a piece of lumber of twenty feet in length, but which piece has only a usable portion of ten feet in length. The excess, which may be on both ends of said piece of lumber, may be removed by depressing two of the saws to a working position. When these saws are not in a working or a sawing position, then they are in an elevated position so as to allow lumber to pass without being sawed. In another instance, a piece of lumber may have so many knots that it is not usable. Then, a combination of saws is depressed to saw the lumber into two-foot lengths so that it may be scrapped. In such a machine, the sa-ws may be placed at two-foot intervals and there may be any usable number of saws. If a sawmill does not saw lumber of long lengths, there may be six or seven saws. If a sawmill saws lumber of exceptionally long lengths, there may be fifteen or twenty saws. Prior to this invention, the sawdust was not completely removed from the vicinity of the saws. For example, there is no way to make certain that the sawdust would be removed from the vicinity of the saws. With this invention I have provided an exhaust hood, a plurality of openings leading to said exhaust hood, a plurality of dampners registering with said openings, a gathering means associated with the saws, and means to open and close a dampner associated with a saw depending upon whether the saw is in a sawing position or elevated out of a sawing position. In this manner it is possible to more effectively use the exhaust hood for removing small solid particles from the vicinity of the saw and thereby keep the working area cleaner than has previously been possible to keep such a working area.

In the drawings it is seen that there is provided a hood 20. The hood 20 is a long, tubular cylinder and has a number of openings 22. The openings 22 extend through an arc of approximately 90 to 100 degrees.

In FIGURE 1 it is seen that there is attached to the exterior of the hood 20, and in the third quadrant, a housing 24. This housing 24 registers with the opening 22 in the hood 20. The housing 24 has an open lower end with two semicircular recesses 26 and also has an open left end as viewed in FIGURE 1. The housing 24 has depending sides 28, and these sides 28 in that portion next to the hood 20 have a semicircular flange 30 for registering and fitting with the outside surface of the hood 20. The sides 28 define the opening registering with the opening 22 of the hood 20 and also define the open bottom and the open end of the housing 24.

In FIGURES and 6 it is seen that near the upper part of the housing 24 and attached to the outer surfaces of the sides 28 are bearings 32. In FIGURE 6 it is seen that the bearings 32 are attached by means of nuts and bolts. In the sides 28 there are openings or passageways. The bearings 32 journal a shaft 34 which passes through the openings in the sides 28. In FIGURE 6 it is seen that the lower end of the shaft 34 projects outwardly from the lower bearings 32. The upper end of the shaft 34 is secured by a nut 36.

In FIGURE 6 it is seen that, on the lower end of the shaft 34, there is an outwardly directed finger 38. This finger 38 comprises a main toroidal shaped base portion 40 which registers with the shaft 34. The finger 38 is directed outwardly and away from the hood 20. The toroidal base 40 may be a force fit or a press fit on the shaft 34. A lever arm 42 is positioned between the finger 38 and the bearing 32 and is free to rotate around the shaft 34. Directed outwardiy from the lever arm 42 is a lug 44. In FIG- URES 7 and 8 it is seen that, when the lever arm 42 rotates in a counterclockwise direction around the shaft 34, the lug 44 contacts the finger 38; and that, when the lever arm 42 rotates in a clockwise direction around the shaft 34, the lug 44 disengages itself from the finger 3-8. The lever arm 42, on its free end, terminates in a pin 46. On the pin 46 there is mounted a roller 48. In the lever arm 42 there is positioned a counterweight 50. The position of the counterweight 50 may be varied as desired.

On the shaft 34 there is mounted a bushing 52. On the bushing 52 there is welded a dampner arm- 54. The dampner arm 54 comprises a main portion 56 which is in the configuration of a semicircular and a small straight portion 58. The main portion 56 and the straight portion 58 are joined by a semicircular portion 60. The semicircular portion 60 curves slightly around the bushing 52 and is welded thereto. On the outer part of the main portion 56 and the dampner arm 54, there is a counterweight 62. The counterweight 62 may be attached by means of bolts as illustrated. The bushing 52 is attached to the shaft 34 by means of 'setscrews 6 as illustrated in FIGURE 6. This definitely positions the dampner arm 54 with respect to the shaft 34 so that when the shaft 34 rotates then the dampner arm 54 rotates. In FIGURE 3 it is seen that the 4 dampner arm 54 generally covers the opening 22 in the hood 20.

Between the sides 28 and in the upper part of the sides, there is positioned a bracket having a short leg 72 attached to the housing 24 by welding and a long leg 74 for supporting a block 76. The block 76 is attached to the long leg 74 by means of a bolt 78. In the long leg 74 and the block 76, there is a drilled passageway 80. A setscrew 82 projects through this drilled passageway and tapped passageway so as to contact the straight portion 58 of the dampner arm 54.

In FIGURES 1 and 2 it is seen that there is a depending lug attached to the outside of the hood 20. The lug 90 is in the fourth quadrant. In FIGURE 9 it is seen that there is a passageway 92 in the lug 90, and this passageway 92 journals a shaft 94. In FIGURE 9 it is seen that, on the left end of the shaft 94, there is a bearing 96 and that a support strap 98 depends from the bearing 96. The support strap 98 connects with a bearing 100. The bearing 100 journals a shaft 102. The other end of the shaft 102 is journalled in a bearing 104. The bearing 104 is attached to the hold-down bar 106. The strap 98 is free to rotate around the shaft 94 and is also free to rotate around the shaft 102. The bearing 104 and the hold-down bar 106 are free to rotate around the shaft 102.

In FIGURE 9 it is seen that, on the right end of the shaft 94, there is a bearing 108. The shaft 94 is journalled in the hearing 108. Also, a strap 110 connects with the bearing 108. This strap 110 has a depending portion 112. The lower end of the depending portion 112 connects with a gathering means or a collector hood 114. A collector hood 114 has sides 116 and an end 118, see FIGURE 9. Also, as illustrated in FIGURES 1 and 2, the left end is opened and is not covered, see FIGURE 5. The lower part of the collector hood 114 is open so as to allow the free entrance of small solid particles. In FIGURES 1 and 2 it is seen that, on the lower right part of the side 116, and that side closer to the viewer, there is attached a pin 120 and on the pin 120 there is a roller 122. The roller rides on the long fiat portion 124 of the hold-down bar 106. It is seen that the strap 110 and the collector hood 114 are free to rotate around the shaft 94. Also, the thickness or width of the collector hood 114 is less than the internal distance between the sides 28 of the housing 24. Therefore, the collector hood 114 can move into and out of the housing 24. The collector hood 114 is in a telescoping relationship with the housing 24.

The working tool is the saw 140. The saw can be lowered to saw a piece of wood and can be raised so as not to be in a sawing position.

There is provided a mounting base 142. This mounting base 142 is a long tubular member as illustrated in FIGURES 1 and 2. An angle 144 connects on the upper portion of the mounting base 142, in quadrant 1, see FIGURES 1 and 2. A table 146 is attached to the angle 144, the upper surface of the base 142 and the upper surface of the hood 20. There is positioned on this table 146 a lifting device for changing the elevation of the saw 142. This lifting device is schematically iilustrated. The lift-device comprises a shaft 148 and a bearing yoke 150. The bearing yoke 150 is in an eccentric relationship with the shaft 148. There is attached to the table 146 a pin 152. A chain 154 is fastened to the pin 152 and runs around the bearing yoke 150. The chain 154 terminates in a turnbuckle or connects with the turnbuckle 156.

In FIGURES 1, 2 and 4 it is seen that, in the lower right portion of the base 142, there are two downwardly and outwardly directed lugs 160. The lugs may be welded to the outside surface of the base or mount 142. In each of the lugs 160, there is a passageway 162. There is positioned in this passageway 162, a trunnion shaft 164. The trunnion shaft 164 is not free to rotate. On each end of the trunnion shaft 164, there is a bearing housing 166. The saw mounting bracket 168 is attached to the bearing housing 166 by means of arms 170. The arms 170 connect with a base 172 of the saw mounting bracket 168. The base 172 connects with a mounting plate 174. The mounting plate 174 is attached to the saw assembly housing 176 by means of bolts 178, see FIGURES 1 and 2. In FIGURES l and 2 it is seen that the saw assembly housing 176 has an upper curved portion 180 which is in the general configuration of a cam and functions as a cam.

There is attached to the saw mounting bracket 168 an adapter 182. The adapter 182 has three spacedapart passageways 184, 186 and 188. The turnbuckle 156 connects with the pin 190 in one of these three passageways. By means of the three passageways 184, 186 and 188, it is possible to easily vary the swing or the length of the arc through which the saw 140 rotates.

The lugs 160 also support a shaft 200. The shaft 200 is journalled in a bearing 202. The shaft 200 is free to rotate in the bearing 202. There depends downwardly from the bearing 202 a support strap 204. The lower end of the support strap 204 connects with a bearing 206. The bearing 206 is housed in a housing 208 and which housing 208 connects with the hold-down bar 106 near the extreme left part of the flat portion 124. The strap 204 is free to rotate with respect to the shaft and bearing 206 and likewise the hold-down bar 106 is free to rotate with respect to the shaft and bearing 206.

In FIGURES 1 and 2 it is seen that there is a trimmer table 210. The trimmer table 210 is positioned below the hold-down bar 106.

The leading edge of the hold-down bar 106, leading edge 212, is curved upwardly so as to allow the incoming lumber 214 to freely enter between the holddown bar 106 and the trimmer table 210.

The trailing edge 216 and the hold-down bar 106 is directed upwardly so as to allow the trimmed lumber to freely move away from between the hold-down bar 106 and the trimmer table 210.

As previously stated, in the use of this means for removing small solid particles from the vicinity of a working tool, there are a plurality of these cleaning means. For example, in the trimmer table in a sawmill there are numerous saws. Generally, the first cut-off saw is always in a swing position. Therefore, there need be no means to raise and lower this saw; and, likewise, no means between the dampner in the sawdust hood for opening and closing the opening 22 in the sawdust hood. This embodiment may be considered to be illustrated in the FIGURE 5 where there is no means for raising and lowering the dampner in FIGURE 5. Likewise, in FIGURE 3 it is seen that the setscrew 82 is adjusted so that the first dampner is open with respect to the opening 22, However, it is to be realized that the other dampners depend upon the position of the saw. If the saw is in a raised or elevated position and not in a sawing position, then the dampner registers with the opening 22 in the hood 20 so as to substantially close said opening 22. And, when the saw 140 is in a lowered and sawing position, then the dampner is removed from the vicinity of the opening 22 so as to allow small solid particles to flow from the vicinity of the saw 140 and in through the opening 22 and into the exhaust hood 20. In this regard, see FIGURE 2, when the saw 140 is in an elevated and out of a sawing position, the arm 42 is rotated so as to be substantially horizontal; and, the dampner is rotated clockwise and downwardly so as to substantially cover the opening 22. Then, when the saw 140 is lowered so as to be in a sawing position, the cam follower roller 48 rolls on the saw housing curved portion 180, so that the arm 42 rotates in a counterclockwise direction and is inclined downwardly, in the third quadrant, with the lug 44 contacting the finger 38 so as to rotate the shaft 34 and the arm dampner counterclockwise and away from the opening 22 so as to allow small solid particles to flow through the opening 22. Likewise, when the saw is raised, the cam follower roller 48 rolls on the curved surface of the saw housing so that the lug 44 disengages with the finger 38 and the weight 62 on the main portion 56 moves the dampner arm 54 so as to cover the opening 22 in the exhaust hood 20.

The hold-down bar 106 can rotate so as to accomdate pieces of lumber 214 of varying thicknesses. For example, the piece of lumber 214 may be one inch thick or may be two inches thick or even thicker. Therefore, with the present arrangement, it is possible to accommodate these pieces of lumber of varying thicknesses. The collector hood or gathering means 114 rides on the hold-down bar 106 by means of the roller 122.

It is seen in FIGURES 1 and 2 that the saw 140 rotates against the direction of movement of the lumber 214 and tends to throw the sawdust into the collector hood 114 and into the housing 24. Because the housing 24 and the collector hood 114 have open ends facing the saw 140, the small solid particles of wood are thrown towards the housing 24 and the collector hood 114.

From the foregoing it is seen that I have provided a means and a method for collecting small solid particles from the vicinity of a working tool so as to keep the working area free of these small solid particles. Also, I have provided a means and method whereby when a working tool is not in working relationship with a solid that the exhaust means is substantially closed so as to make it possible to maintain a greater differential gas pressure between the area of the working tool and exhaust hood so as to assure a more positive flow of small solid particles from the area of the working tool into the exhaust hood.

What I claim is:

1. A means for removing small solid particles from a working area, said means comprising:

(a) a working tool to make said small solid particles from a large solid,

(b) a first gathering means positioned near said working tool;

(c) an exhaust hood;

((1) an opening in said exhaust hood;

(e) a housing attached to said exhaust hood and surrounding said opening to direct said small solid particles through said opening and into said exhaust hood;

(f) said first gathering means positioned with respect to said housing to direct said small solid particles into said housing;

(g) said exhaust hood positioned near said working tool;

(h) a second means to have the gas pressure in said exhaust hood at a lower pressure than the gas pressure in the vicinity of said working tool so that the small solid particles will move from the vicinity of the working tool to the exhaust hood; and

(i) a third means to control the flow of gas from the vicinity of said working tool through said first gathering means and into said exhaust hood.

2. A means for removing small solid particles according to claim 1 and comprising:

(a) said third means comprising a dampner; and

(b) said dampner fitting with said opening in said exhaust hood.

3. A means for removing small solid particles according to claim 1 and comprising:

a) a fourth means to vary the position of the working tool; and

(b) a fifth means to position the large solid with respect to the working tool.

4. A means for removing small solid particles according to claim 2 and comprising:

(a) fourth means to vary the position of the working tool; and

(b) a fifth means connecting with the third means and responsive to the position of the working tool to vary the position of the third means with respect to the opening in said exhaust hood.

5. A means for removing small solid particles according to claim 1 and comprising:

(a) said working tool being a saw;

(b) said first gathering means being a collector hood;

(c) said third means comprising a dampner; and

(d) said dampner fitting with said opening in said exhaust hood.

6. A means for removing small solid particles according to claim 5 and comprising:

(a) a fourth means to vary the postion of the working tool; and

(b) a fifth means connecting with the third means and responsive to the position of the working tool to vary the position of the third means with respect to the opening in said exhaust hood.

7. A means for removing small solid particles according to claim 6 and comprising:

(a) a shaft;

(b) said dampner rotating about said shaft;

(c) a cam associated with said working tool; and

((1) said fifth means comprising a cam follower for following the movement of said cam so as to vary the position of the dampner.

8. A means for removing small solid particles according to claim 5 and comprising:

(a) a hold-down bar to position the large solid with respect to the saw.

9. A means for removing small solid particles according to claim 5 and comprising:

(a) a hold-down bar to position the large solid with respect to the saw; and

(b) a pivot means connecting with said hold-down bar to allow said hold-down bar to accommodate various sizes of said large solid.

10. A means for removing small solid particles according to claim 5 and comprising:

(a) a hold-down bar to position the large solid with respect to the saw; and

(b) a pivot means connecting with said means for removing small solid particles and to allow said holddown bar to move to accommodate various sizes of said large solid.

11. A means for removing small solid particles according to claim 5 and comprising:

(a) said collector hood being rotatable to accommodate various sizes of said large solid.

12. A means for removing small solid particle according to claim 5 and comprising:

(a) a housing attached to said exhaust hood and connecting with said opening in said exhaust hood; and

(b) said collector hood connecting with said housing.

13. A means for removing small solid particles according to claim 5 and comprising:

(a) a housing attached to said exhaust hood and connecting with said opening in said exhaust hood;

(b) said collector hood connecting with said housing;

(c) a shaft attached to said housing;

((1) said collector hood connecting with said shaft so as to rotate around said shaft to accommodate various sizes of said large solid;

(e) a hold-down bar to position the large solid with respect to the saw;

(f) a pivot means connecting with said hold-down bar to allow said hold-down bar to accommodate various sizes of said large solid; and

(g) said collector hood riding on said hold-down bar.

14. A means for removing small solid particles according to claim 7 and comprising:

(a) a motor for driving said saw;

(b) a housing for said motor; and

(c) said housing being said cam.

15. A means for removing small solid particles according to claim 5 and comprising:

(a) said collector hood having an opening facing said saw so as to enclose a portion of said saw; and

(b) said saw rotating in the direction of said collector hood as to direct the small solid particles toward said collector hood.

16. A means for removing small solid particles from a working area, said means comprising:

(a) a plurality of working tools to make said small solid particles from a large solid;

(b) a first gathering means positioned near each of said working tools;

(c) an exhaust hood;

(d) a plurality of openings in said exhaust hood and positioned near said first gathering means;

(e) a plurality of housings attached to said exhaust hood and surrounding said openings to direct said small solid particles through said openings and into said exhaust hood;

(f) said first gathering means positioned with respect to said housing to direct said small solid particles into said housing;

(g) said exhaust hood positioned near said working tool;

(h) a second means to have the gas pressure in said exhaust hood at a lower pressure than the gas pressure in the vicinity of said working tool so that the small solid particles will move from the vicinity of the working tool to the exhaust hood; and

(i) a third means to control the flow of gas from the vicinity of each said working tool through each said first gathering means and into said exhaust hood.

17. A means for removing small solid particles according to claim 16 and comprising:

(a) said third means comprising a plurality of dampners; and

(b) said dampners registering with said openings in said exhaust hood.

18. A means for removing small solid particles according to claim 17 and comprising:

(a) a fourth means to selectively vary the position of the working tools.

19. A means for removing small solid particles according to claim 18 and comprising:

(a) a plurality of fifth means connecting with the third means and responsive to the positions of the working tools to vary the positions of the third means with respect to the openings in said exhaust hood.

20. A means for removing small solid particles according to claim 16 and comprising:

(a) said working tools being saws;

(b) said first gathering means being collector hoods;

(c) said third means comprising dampners; and

(d) said dampners fitting With said openings in said exhaust hood.

21. A means for removing small solid particles from a working area, said means comprising:

(a) working tool to make said small solid particles from a large solid;

(b) an exhaust hood;

(c) an opening in said exhaust hood;

(d) a housing attached to said exhaust hood and surrounding said opening to direct said small solid particles through said opening and into said exhaust hood;

(e) a collector hood positioned with respect to said housing to direct said small solid particles into said housing;

(f) a dampner for fitting with said opening to regulate the flow of gas and said small solid particles through said opening;

(g) an arm connecting with said dampner;

(h) said arm operatively connecting with said working tool;

(i) with said working tool and said arm in a first position said dampner covering said opening and with said working tool and said arm in a second position said dampner removed from said opening to allow gas and said small solid particles to flow through said opening;

(j) a means to vary the position of said working tool;

and

(k) a means to have the gas pressure in said exhaust hood at a lower pressure than the gas pressure in the vicinity of said working tool so that the small solid particles will move from the vicinity of the working tool to the exhaust hood.

22. A means according to claim 21 and comprising:

(a) a cam operatively connecting with said working tool; and

(b) a cam follower on said arm for following the movements of said working tool and said cam.

23. A means according to claim 22 and comprising:

(a) a plurality of said working tools;

(b) a plurality of said openings with operatively con nccting said working tools;

(c) a plurality of said housings operatively connecting with said openings;

(d) a plurality of said collector heads operatively connecting with said housings;

(e) a plurality of dampners operatively connecting with said openings;

(f) a plurality of arms operatively connecting with said dampners; and

(g) a plurality of cams operatively connecting with said working tools and with said arms.

References Cited UNITED STATES PATENTS 1,552,553 9/1925 Georgia l4341 X 3,036,605 5/1962 Joa 14341 3,167,260 1/1965 Gibbons 143157 X 3,339,597 9/1957 Kohler 143-157 X 20 HARRISON L. HINSON, Primary Examiner US. Cl. X.R. 

